It is the statutory duty of Police to investigate into a complaint of cognizable offence. Police investigation is not only a statutory duty but also a constitutional obligation of the Police.
“24. In the criminal justice system the investigation of an offence is the domain of the police. The power to investigate into the cognizable offences by the police officer is ordinarily not impinged by any fetters. However, such power has to be exercised consistent with the statutory provisions and for legitimate purpose. The courts ordinarily do not interfere in the matters of investigation by police, particularly, when the facts and circumstances do not indicate that the investigating officer is not functioning bona fide. In very exceptional cases, however, where the court finds that the police officer has exercised his investigatory powers in breach of the statutory provision putting the personal liberty and/or the property of the citizen in jeopardy by illegal and improper use of the power or there is abuse of the investigatory power and process by the police officer or the investigation by the police is found to be not bona fide or the investigation is tainted with animosity, the court may intervene to protect the personal and/or property rights of the citizens.
Supreme Court
Manohar Lal Sharma vs. Principal Secretary & Ors., (2014) 2 SCC 532
7. We are constrained to record that the investigation and the closure report are extremely casual and perfunctory in nature. The investigation and closure report do not contain any material with regard to the nature of investigation against the other accused including respondent no.5 for conspiracy to arrive at the conclusion for insufficiency of evidence against them. The closure report is based on the ipse dixit of the Investigating Officer. The supervision note of the Senior Superintendent of Police (Rural), in the circumstances leaves much to be desired. The investigation appears to be a sham, designed to conceal more than to investigate. The police has the primary duty to investigate on receiving report of the commission of a cognizable offence. This is a statutory duty under the Code of Criminal Procedure apart from being a constitutional obligation to ensure that peace is maintained in the society and the rule of law is upheld and applied. To say that further investigation was not possible as the informant had not supplied adequate materials to investigate, to our mind, is a preposterous statement, coming from the police.
8. The police has a statutory duty to investigate into any crime in accordance with law as provided in the Code of Criminal Procedure. Investigation is the exclusive privilege and prerogative of the police which cannot be interfered with. But if the police does not perform its statutory duty in accordance with law or is remiss in the performance of its duty, the court cannot abdicate its duties on the precocious plea that investigation is the exclusive prerogative of the police. Once the conscience of the court is satisfied, from the materials on record, that the police has not investigated properly or apparently is remiss in the investigation, the court has a bounden constitutional obligation to ensure that the investigation is conducted in accordance with law. If the court gives any directions for that purpose within the contours of the law, it cannot amount to interference with investigation. A fair investigation is, but a necessary concomitant of Articles 14 and 21 of the Constitution of India and this Court has the bounden obligation to ensure adherence by the police.
Supreme Court
Amar Nath Chaubey vs Union of India and Ors., AIR 2021 Supreme Court 109